MOLECULAR MECHANISMS--BACTERIAL ADHERENCE TO CEMENTUM

分子机制——细菌对牙骨质的粘附

• 批准号: 6634606
• 负责人: SUSAN J. FISHER
• 金额: $ 29.01万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-04-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6634606
• 关键词: SDS polyacrylamide gel electrophoresis; binding proteins; carbohydrate receptor; carbohydrate structure; cell adhesion; cementum; glycopeptides; glycoprotein structure; glycoproteins; high performance liquid chromatography; host organism interaction; human subject; lectin; mass spectrometry; mucins; nuclear magnetic resonance spectroscopy; oligosaccharides; oral bacteria; pellicle; receptor binding; saliva; species difference

One of the most interesting and biologically important functions of salivary glycoproteins is their ability to serve as bacterial receptors. Although microbial adhesion too the tooth surface and/or clearance from the oral cavity is the result of a complex interplay of many factors, interactions between bacterial proteins (e.g., adhesins, lectins) and the carbohydrate portions of salivary molecules are often an important component of the process. The long-term goal of this project is to use information about the structure of these carbohydrate receptors to design molecules that mimic or inhibit receptor activity: these might be used to modulate the composition of the oral flora. Our generalized experimental strategy for ultimately accomplishing this goal includes the following steps. First, we plan to create a library of the carbohydrate structures carried by salivary glycoproteins. Next we will use this information to determine the unique aspects of these structures that confer bacterial receptor activity to the proteins they modify. Then we will measure the binding force of these adhesive interactions, one means of determining their biological relevance. Here, we apply this experimental strategy to study adhesive interactions between the low molecular weight salivary mucin (MG2) and several species of oral bacteria. We are focusing our efforts on MG2 because our previous work demonstrated its dual role as a bacterial receptor and a major glycosylated pellicle component that could mediate the initial stages of microbial adhesion to the tooth surface. Specifically, we will; 1. Determine the complete structure of the N- and O-linked carbohydrate chains carried by MG2. 2. Establish the aspects of MG2 oligosaccharide structure that specify receptor activity for the bacteria we have shown to interact with this glycoprotein. 3. Determine the relative strength of mG2-bacterial interactions by using a centrifugal force adhesion assay. Using structural information about carbohydrate receptors to design compounds that modify and microbial adhesion presents several interesting challenges and opportunities. One interesting challenge is to design univalent inhibitors that have higher affinities than the natural carbohydrate receptors recognized by bacterial ligands. Another approach, possible when carbohydrate receptors are multivalent, is to produce synthetic compounds that increase the number or optimize the spacing of binding epitopes. Altering oral microbial adhesion also presents an interesting opportunity for drug delivery. In this specialized environment, topical application obviates the need for systemic adsorption. This greatly simplifies the design of artificial salivary molecules that mimic the natural bacterial receptor activity of this fluid, as well as competitive inhibitors of plaque formation.

最有趣和生物学上最重要的功能之一 唾液糖蛋白是它们充当细菌受体的能力。 尽管微生物粘附也是牙齿表面和/或从 口腔是许多因素的复杂相互作用的结果， 细菌蛋白（例如粘附素，凝集素）与 唾液分子的碳水化合物部分通常是重要的 过程的组成部分。 该项目的长期目标是使用 有关这些碳水化合物受体的结构的信息 模仿或抑制受体活性的分子：这些可以用于 调节口腔菌群的组成。 我们广泛的实验 最终实现此目标的策略包括以下 步骤。 首先，我们计划创建一个碳水化合物结构的库 由唾液糖蛋白携带。 接下来，我们将使用此信息来 确定赋予细菌的这些结构的独特方面 受体活性对它们修饰的蛋白质。 然后我们将测量 这些粘合剂相互作用的结合力，一种确定的方法 它们的生物学相关性。 在这里，我们将此实验策略应用于 研究低分子量唾液粘蛋白​​之间的粘合剂相互作用 （MG2）和几种口服细菌。 我们将精力集中在 MG2，因为我们以前的工作表现出其双重作用作为细菌 受体和主要的糖基化细胞成分，可以介导 微生物粘附到牙齿表面的初始阶段。 具体来说， 我们将; 1。确定N-和O链接的完整结构 MG2携带的碳水化合物链。 2。建立MG2的各个方面 指定细菌受体活性的寡糖结构 我们已经证明可以与这种糖蛋白相互作用。 3。确定 通过使用离心机的MG2 - 细菌相互作用的相对强度 力粘附测定。 使用有关碳水化合物受体设计的结构信息 修饰和微生物粘附的化合物表现出几种有趣的 挑战和机遇。 一个有趣的挑战是设计 具有高亲和力的单价抑制剂 细菌配体识别的碳水化合物受体。 另一种方法， 当碳水化合物受体是多价时，可能会产生 合成化合物增加数量或优化的间距 结合表位。 改变口腔微生物粘附也表明 吸毒的有趣机会。 在这个专业中 环境，局部应用避免了全身吸附的需求。 这大大简化了人工唾液分子的设计 模仿这种液体的天然细菌受体活性，以及 斑块形成的竞争抑制剂。